DMD 1.027 and 2.011 releases

[eao197]

On Mon, 25 Feb 2008 12:44:15 +0300, Walter Bright  
<newshound1 at digitalmars.com> wrote:

> Ary Borenszweig wrote:
>> Does this mean this will not compile:
>>  int foo(int[] someArray, int someIndex) nothrow {
>>     return someArray[someIndex];
>> }
>>  but this will:
>>  int foo(int[] someArray, int someIndex) nothrow {
>>     if (someIndex < someArray.length) {
>>         return someArray[someIndex];
>>     } else {
>>         return -1;
>>     }
>> }
>
> I don't know yet. But the idea is to do static checking of what can  
> throw.

Just my $0.02 about nothrow and DesignByContract: I think that nothrow are  
incompatible with DbC. A function/method could have contracts or nothrow  
but not both of them. It is especially actual for virtual (non-final)  
methods. Suppose that some class has:

class A {
   public void cleanup() nothrow { ... };
}

so it could be safely used in 'finally' statement:

A someResource = acquireResource();
try { ... /* some processing */ ... }
finally {
   someResource.cleanup; /* looks like exception-safe action */
}

But if there is a derived class B, which overrides cleanup() with  
postcondition:

class B : A {
   public void cleanup() nothrow
     out { ... some checking ... }
     body { ... some actions ... }
}

and acquireResource() would return B instead of A, then the code above  
won't be exception-safe. Moreover the behaviour of 'someResource.cleanup'  
would depend on compiler switches.

-- 
Regards,
Yauheni Akhotnikau